#include <stdio.h>

int main(void)
{
   int b[6] = {23,12,7,9,18,4};
   int i,j = 0;
   for (i = 0;i < 3;i++)
   {	   
       j = b[i]; 
       b[i] = b [5-i];
       b[5-i] = j;
   }
   for (i = 0;i < 6;i++)
   {	   
       printf("b[i]=%d\n",b[i]);   
   }
    return 0;
}	
